300 Gallon Tank

[MGRigby]

I'm going to try not to make this too long but I need help on this one.  I have a friend that I kinda lost contact with and heard he had opened an outdoor supply store in the area and went in today to check it out.  To my surprise he had a 300 gallon tank built in the wall.  It looks terrible!  I would say about 200 lbs. live (dead) rock,  running two oceanview canister filters,  huge crushed coral for a substrate, and two 72" fluor. not sure if vho or no.  No sump, brown nasty looking algae, I'm sure tap water.  He was busy and basically said he kills everything he puts in there.  Not hard to see why.  He would love to get it right and I would love to help him.  Where do I start?  Not sure of what to use for water movement, lighting, skimmer, should I use ozone,  do I need to take everything out of the ! tank, clean and start over.  What to use for sump, return pump, etc.  He has probably spent enough on dead livestock, etc. to have done it right from the get go but didn't have the help that I have had on mine.  There is room above to hang lights, (maybe pendents).  Sure there is more to consider but this will get me started.  Would love to keep you all posted on the progress and am looking forward to being able to help set it up with someone else's money.  Were do I start? Glen